1. Field of the Invention
This invention relates generally to a record player, and more particularly is directed to a record player turntable integrally provided with at least part of an electric motor for driving the same.
2. Description of the Prior Art
In a conventional phonograph record player, a turntable is driven by an electric motor, either by direct drive, or through a belt or other transmission. Even in a direct-drive turntable assembly, a separate motor is provided. Typically, to obtain maximum performance, the turntable of a record player is driven by a DC brushless motor which usually includes a permanent-magnet rotor and a coil stator. The motor is aligned with the axis of the turntable and connected thereto by a motor shaft that can also form the spindle of the turntable.
In such a direct-drive arrangement, the motor and other parts of the drive assembly require a significant amount of space in the vertical direction. Conventional phonographs must be constructed so as to accomodate the vertical dimension of the motor and drive assembly, and, as a result, the vertical dimension of such phonographs is required to be many times as great as the thickness of the turntable itself. Also, in conventional phonograph record players, the diameter of the motor is relatively small. Thus, the permanent magnet associated with the rotor has to be highly magnetized, and a relatively high current has to be supplied to the coil in order to produce sufficient torque for rotating the turntable. Such rotor and coil can produce flux leakage which can, in turn, produce noise in a magnetic pickup cartridge used in conjunction with the phonograph.